I have 2 or 3 ground blinds that I hunt out of. I have only used them the last couple years. I usually put them in the edge of the woods and try to blend them in to the surroundings by weeds, brush, etc. or place them under a low hanging tree.

I have been wondering lately if anyone has ever simply placed them out in the open in a field or grass area, etc. Simply 60-100 rows outside the woods in a corn or bean field? Obviously this would have to be done well in advance of actual hunting season for the deer to get used to it being there. I have actually seen deer here that will gather around things left in fields, like wagons, tractors and other farm equipment.

Have anyone ever tried not hiding your blind and simply placing it in the wide open in a field?

I hunt in a ground blind all the time an no i have not tried that. To your point, if you left it out there long enough it might be OK. I know of a few places around here that people have built large elevated box blinds and placed them in the middle of fields and have very good success.
The blind would have to be left out for a long time and would have to be of a quality that could stand to be out in the sun and conditions that long

Never done that with portable ground blinds, but have built several permanent box blinds, you can put them anywhere you want and waita week at least before you hunt it.That's all it takes for them to get used to it.